Wideband, Strange readings
Discussion
I recently fitted a wideband to my car.
When the car is started cold it reads around 12 to 13 afr, if left to warm up it will them read 14-15 which is about right.
But, if i take the car out and give it a few hard pulls, then stop, it idles at around 17, and then if i drive it around at a normal pace, the needle reads off the clock past 18, and will come down to 15 when on boost.
If i switch the car off then on again, the afr's read 14-15 again on idle.
What could be the problem, im pretty sure that the readings are wrong, as if the car was running these afr's it would have blown up by now.
When the car is started cold it reads around 12 to 13 afr, if left to warm up it will them read 14-15 which is about right.
But, if i take the car out and give it a few hard pulls, then stop, it idles at around 17, and then if i drive it around at a normal pace, the needle reads off the clock past 18, and will come down to 15 when on boost.
If i switch the car off then on again, the afr's read 14-15 again on idle.
What could be the problem, im pretty sure that the readings are wrong, as if the car was running these afr's it would have blown up by now.
Its wired as per instructions,
2x red wires with constant 12v and 5a fuse
1x wire from ignition
1x wire from lights
1x ground
Its mounted in front of the flexi at the bottom of the decat, at a 2 o'clock position.
I tried swapping its position with the lambs sensor but got the same readings
2x red wires with constant 12v and 5a fuse
1x wire from ignition
1x wire from lights
1x ground
Its mounted in front of the flexi at the bottom of the decat, at a 2 o'clock position.
I tried swapping its position with the lambs sensor but got the same readings
Edited by Weyro on Tuesday 7th August 10:52
Weyro said:
Its wired as per instructions,
2x red wires with constant 12v and 5a fuse
1x wire from ignition
1x wire from lights
1x ground
Its mounted in front of the flexi at the bottom of the decat, at a 2 o'clock position.
I tried swapping its position with the lambs sensor but got the same readings
Where are those connections sourced is more pertinent.2x red wires with constant 12v and 5a fuse
1x wire from ignition
1x wire from lights
1x ground
Its mounted in front of the flexi at the bottom of the decat, at a 2 o'clock position.
I tried swapping its position with the lambs sensor but got the same readings
Edited by Weyro on Tuesday 7th August 10:52
If you're not using the ECU's 12v supply and ECU grounds, and from as close to the ECU as you can get you are suffering from ground offsets.
i.e. switched 12v from the fag lighter socket and the ground wrapped around a random bolt on the chassis is no where near good enough.
Weyro said:
I recently fitted a wideband to my car.
When the car is started cold it reads around 12 to 13 afr, if left to warm up it will them read 14-15 which is about right.
But, if i take the car out and give it a few hard pulls, then stop, it idles at around 17, and then if i drive it around at a normal pace, the needle reads off the clock past 18, and will come down to 15 when on boost.
If i switch the car off then on again, the afr's read 14-15 again on idle.
What could be the problem, im pretty sure that the readings are wrong, as if the car was running these afr's it would have blown up by now.
Of course no mention of what wideband, what kit, what car, what engine, what state of tune etc etc etc.When the car is started cold it reads around 12 to 13 afr, if left to warm up it will them read 14-15 which is about right.
But, if i take the car out and give it a few hard pulls, then stop, it idles at around 17, and then if i drive it around at a normal pace, the needle reads off the clock past 18, and will come down to 15 when on boost.
If i switch the car off then on again, the afr's read 14-15 again on idle.
What could be the problem, im pretty sure that the readings are wrong, as if the car was running these afr's it would have blown up by now.
Also worth mentioning (once you sort out the wiring), if you run too rich or have incomplete combustion the wideband will get saturated, for want of a better word and show a false lean condition. My wideband sensor became more and more sensitive to a slightly rich mixture until it failed.
Weyro said:
12v constant is straight from battery, wired by me
But switched and earth are both from wires that were put in by previous owner for boost gauge.
Will I earth it straight to the battery?
No, re read my previous post and wire like that.But switched and earth are both from wires that were put in by previous owner for boost gauge.
Will I earth it straight to the battery?
Straight to the battery you'll still have a ground offset.
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